FIRST RECORD OF AN EXOTIC TRICHODINID CILIOPHORAN (CILIOPHORA: TRICHODINIDAE) Trichodina modesta Lom, 1970 FROM AN INDIAN GANGETIC LEAFFISH Nandus nandus (HAMILTON, 1822)
AMLAN KUMAR MITRA *
Department of Zoology, Ranaghat College, P.O. Ranaghat, District. Nadia, West Bengal, Pin-741201, India.
*Author to whom correspondence should be addressed.
Abstract
Nandus nandus, often known as the Gangetic leaffish, is an Asian leaffish species native to South Asia and Indochina. They are commonly found in slow-moving or stagnant bodies of water such as ponds, lakes, ditches, and flooded fields. The species is also known as speckled nandus and mud perch. This species was tested for parasite infestations in various species of freshwater fish in the river Ganges. For taxonomic evaluation, parasite smears were treated with silver nitrate. Disc-shaped trichodinids were discovered with a body diameter of 28.5-31.6 µm, adhesive disc diameter of 19.3-25.5 µm, and denticulate ring diameter of 11.2-16.8 µm. The physical traits were similar to those of Trichodina modesta Lom, 1970, a species with a strong host preference for Cypriniformes. Until recently, it was only found in the Eurasian region. The current study reports a new host for T. modesta and thus the first occurrence of this species in India. The parasite may have entered the Oriental region via the exotic fish trade, specifically Cypriniformes utilized by aquarists.
Keywords: Trichodina modesta, ectoparasite, fish, Nandus nandus, West Bengal